[sweetbmxrider]

To put a ’96 4L60E into a ’94 car: The ’94 tailshaft housing and VSS must be installed on the ’96 4L60E before the trans can be bolted into the car. Mod A must be performed. The trans will operate normally without Mod A but TCC lockup will not work, so highway and cruising gas mileage will suffer and more heat will be produced in the transmission.

TCC Mod (method 1):
An additional wire must be run from the PCM connector D pin 6 to pin "U" on the trans harness for the TCC to work. Also, the PCM must be reprogrammed with ’95 transmission base code. In my opinion this is more work than its worth due to the amount of labor involved in properly routing an additional wire into the powertrain wiring harness.

TCC Mod (method 2):
Leave the PWM solenoid unplugged but installed. On the valve directly to the right of the PWM solenoid – push that valve all the way towards the outside of the valvebody, and stake it into place. That’ll lock keep the valve acted on by the PWM in the full-open position and it’ll function like a '94 style lockup. No PCM reprogramming required. Now with pics! You may have to swap the ’94 internal harness into '95-’96 transmission, but I'm not sure. I recommend not swapping harnesses if you don't have to, because they will most likely be brittle and are tricky to remove from the case without damaging the lugs on the connector.

for what its worth

"mod a"

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